碱对AlMCM-41介孔分子筛合成的影响

分别用NaOH和TEAOH合成了AlMCM 4 1介孔分子筛 ,用XRD、2 7AlMASNMR、SEM、TEM、IR、N2 低温吸附和TG DTA对样品进行了表征和比较。结果表明 ,TEAOH和NaOH对AlMCM 4 1有序结构的影响不同。当硅铝原子比为 2 5或 5 0时 ,用NaOH合成的样品有序性较高 ;而当硅铝比为 15时 ,用TEAOH合成的样品有序性较高。交换成氢型AlMCM 4 1后 ,当硅铝比为 2 5或 15时 ,用TEAOH合成的样品抗水解性能优于用NaOH合成的样品 ,其酸量也较大。用TEAOH合成的样品粒度小 ,比表面积、孔径和孔体积都大于用NaOH合成的样品

EFFECT OF ALKALI ON THE SYNTHESIS OF AIMCM-41 MESOPOROUS MOLECULAR SIEVES

AlMCM 41 mesoporous molecular sieves were synthesized in the presence of NaOH or TEAOH, and were characterized by XRD, 27 Al MAS NMR, SEM, TEM, IR, low temperature N 2 adsorption and TG DTA methods. Results showed that organic alkali was different from inorganic alkali in the effect on structure orderliness of AlMCM 41, which appeared higher when the sample was prepared by NaOH with Si/Al atomic ratios of 25 or 50. However,those samples with Si/Al ratio of 15 prepared by TEAOH showed highest structure orderliness. The H AlMCM 41 samples with Si/Al ratios of 25 or 15 prepared by TEAOH were more resistant to hydrolysis and showed higher acidity than those synthesized by NaOH. The samples prepared by TEAOH formed smaller grain, while their diameter, BET specific surface area and pore volume were higher than those synthesized by NaOH.